fix(reader): read position from the API at open; never write a restored position

The reader page embedded a snapshot of reading state (position,
bookmarks) server-side at render time. Browsers may reuse that HTML
(heuristic caching, bfcache), so opening a book could restore a stale
position — and worse, the restore's relocate auto-saved it back,
overwriting a newer device push minutes later. A KOReader sync followed
by opening the web reader would silently revert the row to the old web
position; the row's source and the rendered page disagreed.

The web reader is intrinsically tied to the server, so it has no business
preserving reading state client-side:

- The rendered page now carries only immutable book metadata. The reader
  fetches progress fresh (cache: no-store) from the existing progress
  API at open and restores with the same priority as before (page for
  fixed-layout, CFI, percentage, fresh start); a failed fetch opens at
  the start and writes nothing. Initial bookmarks likewise come from
  their endpoint instead of the embed; annotations already did.
- Progress saves are gated on deliberate navigation only (page turns,
  keys, slider, search/TOC/bookmark/back-stack jumps, tap zones — each
  marks the session as user-moved). Restores and section-load
  relocations never write, so displaying a position can no longer
  clobber a newer one. A bfcache-resurrected page resets the flag and
  cannot write its frozen position either. This replaces the old
  five-second post-init suppression, which a stale page bypassed.
- The server-rendered initial progress badges render a neutral
  placeholder until the first relocate fills them (sub-second).

No API, schema, or sync-engine changes. Normal reading saves exactly as
before — the first save now simply waits for the first real page turn.

internal/router/reader.go

@@ -1,18 +1,15 @@
 package router
 
 import (
-	"bookhoard/internal/database"
 	"bookhoard/internal/handlers"
 	"bookhoard/internal/services"
 	"bookhoard/internal/sync"
 	"bookhoard/internal/utils"
 	"bookhoard/templates"
 	"bytes"
-	"errors"
 	"net/http"
 
 	"github.com/google/uuid"
-	"github.com/jackc/pgx/v5"
 	"github.com/jackc/pgx/v5/pgtype"
 	"github.com/labstack/echo/v5"
 )
@@ -69,21 +66,10 @@ func registerReaderRoutes(cfg *Config) {
 		if !visible {
 			return renderErrorPage(c, "Access denied", "access_denied")
 		}
-		// Get reading progress
-		var progress database.ReadingProgress
-		progress, err = cfg.Queries.GetReadingProgress(c.Request().Context(), database.GetReadingProgressParams{
-			MediaItemID: pgtype.UUID{Bytes: parsedUUID, Valid: true},
-			UserID:      uuidToPGType(userUUID),
-		})
-		if err != nil && !errors.Is(err, pgx.ErrNoRows) {
-			progress = database.ReadingProgress{}
-		}
-		// Get bookmarks
-		bookmarks, _ := cfg.Queries.GetMediaBookmarks(c.Request().Context(), database.GetMediaBookmarksParams{
-			MediaItemID: pgtype.UUID{Bytes: parsedUUID, Valid: true},
-			UserID:      uuidToPGType(userUUID),
-		})
-		// Convert to template types
+		// Convert to template types. Reading state is deliberately NOT
+		// fetched or embedded: the reader pulls position, bookmarks, and
+		// annotations from the APIs at open time so the page can never
+		// carry (nor write back) a stale snapshot.
 		mediaUUID, _ := uuid.FromBytes(mediaItem.ID.Bytes[0:16])
 		libUUID, _ := uuid.FromBytes(mediaItem.LibraryID.Bytes[0:16])
 		metadata := templates.ReaderMetadata{
@@ -104,58 +90,9 @@ func registerReaderRoutes(cfg *Config) {
 			TotalCharacters:  mediaItem.TotalCharacters.Int64,
 			EstimatedPages:   sync.EstimatedPages(mediaItem.TotalCharacters.Int64),
 		}
-		// Progress conversion (inline)
-		progressUUID, _ := uuid.FromBytes(progress.ID.Bytes[0:16])
-		progressMediaUUID, _ := uuid.FromBytes(progress.MediaItemID.Bytes[0:16])
-		progressUserUUID, _ := uuid.FromBytes(progress.UserID.Bytes[0:16])
-		templateProgress := templates.ReadingProgress{
-			ID:              progressUUID.String(),
-			MediaItemID:     progressMediaUUID.String(),
-			UserID:          progressUserUUID.String(),
-			CurrentPage:     int(progress.CurrentPage.Int32),
-			TotalPages:      int(progress.TotalPages.Int32),
-			Percentage:      progress.Percentage.Float64 * 100,
-			EpubCfi:         textToString(progress.Epubcfi),
-			LastReadAt:      progress.LastReadAt.Time,
-			Chapter:         int(progress.Chapter.Int32),
-			ChapterProgress: progress.ChapterProgress.Float64 * 100,
-			FormatGroup:     mediaItem.FormatGroup,
-		}
-		// Bookmarks conversion (inline, with loop)
-		templateBookmarks := make([]templates.Bookmark, len(bookmarks))
-		for i, b := range bookmarks {
-			bookmarkUUID, _ := uuid.FromBytes(b.ID.Bytes[0:16])
-			bookmarkMediaUUID, _ := uuid.FromBytes(b.MediaItemID.Bytes[0:16])
-			bookmarkUserUUID, _ := uuid.FromBytes(b.UserID.Bytes[0:16])
-
-			var pageNumber *int
-			if b.PageNumber.Valid {
-				val := int(b.PageNumber.Int32)
-				pageNumber = &val
-			}
-
-			var chapterNumber *int
-			if b.ChapterNumber.Valid {
-				val := int(b.ChapterNumber.Int32)
-				chapterNumber = &val
-			}
-
-			templateBookmarks[i] = templates.Bookmark{
-				ID:            bookmarkUUID.String(),
-				MediaItemID:   bookmarkMediaUUID.String(),
-				UserID:        bookmarkUserUUID.String(),
-				PageNumber:    pageNumber,
-				ChapterNumber: chapterNumber,
-				CfiPosition:   textToString(b.CfiPosition),
-				Title:         b.Title,
-				Position:      textToString(b.Position),
-				Notes:         textToString(b.Notes),
-				CreatedAt:     b.CreatedAt.Time,
-			}
-		}
-		// 8. Render template
+		// Render template
 		var buf bytes.Buffer
-		err = templates.Reader(user, metadata, templateProgress, templateBookmarks).Render(c.Request().Context(), &buf)
+		err = templates.Reader(user, metadata).Render(c.Request().Context(), &buf)
 		if err != nil {
 			return renderErrorPage(c, "Error rendering reader", "render_error")
 		}